Intel E6700 Mechanical Design Guidelines - Page 103

Balanced Technology Extended (BTX) System Thermal Considerations

Thermal and Mechanical Design Guidelines

103

Appendix E

Balanced Technology

Extended (BTX) System

Thermal Considerations

There are anticipated system operating conditions in which the processor power may

be low but other system component powers may be high. If the only Fan Speed

Control (FSC) circuit input for the Thermal Module Assembly (TMA) fan is from the

processor sensor then the fan speed and system airflow is likely to be too low in this

operating state. Therefore, it is recommended that a second FSC circuit input be

acquired from an ambient temperature monitor location within the system.

The location of the System Monitor thermal sensor is best determined through

extensive system-level numerical thermal modeling or prototype thermal testing. In

either case, the temperature of critical components or the air temperature near critical

components should be assessed for a range of system external temperatures,

component powers, and fan speed operating conditions. The temperature at the

selected location for the System Monitor Point should be well correlated to the

temperatures at or near critical components. For instance, it may be useful to monitor

the temperature near the PSU airflow inlet, near the graphics add-in card, or near

memory.

The final system integrator is typically responsible for ensuring compliance with the

component temperature specifications at all operating conditions and, therefore,

should be responsible for specifying the System Monitor thermal sensor location.

However, it is not always possible for a board supplier – especially a channel board

supplier – to know the system into which a board will be installed. It is therefore

important for BTX board suppliers to select a System Monitor thermal sensor location

that will function properly in most systems.

A BTX system should be designed such that the TMA exhaust is the primary airflow

stream that cools the rest of the system. The airflow passes through the chipset

heatsink and its temperature will rise as the memory controller chipset power

increases. Since chipset power will increase when other subsystems (such as,

memory, graphics) are active, a System Monitor thermal sensor located in the exhaust

airflow from the chipset heatsink is a reasonable location.

It is likely that a thermal sensor that is not mounted above the board and in the

chipset exhaust airflow will reflect board temperature and not ambient temperature. It

is therefore recommended that the Thermal sensor be elevated above the board.

Section	Page
1 Introduction	9
1.1 Document Goals and Scope	9
1.1.1 Importance of Thermal Management	9
1.1.2 Document Goals	9
1.1.3 Document Scope	10
1.2 References	11
1.3 Definition of Terms	11
2 Processor Thermal/Mechanical Information	13
2.1 Mechanical Requirements	13
2.1.1 Processor Package	13
2.1.2 Heatsink Attach	15
2.1.2.1 General Guidelines	15
2.1.2.2 Heatsink Clip Load Requirement	15
2.1.2.3 Additional Guidelines	16
2.2 Thermal Requirements	16
2.2.1 Processor Case Temperature	16
2.2.2 Thermal Profile	17
2.2.3 Thermal Solution Design Requirements	17
2.2.4 TCONTROL	18
2.3 Heatsink Design Considerations	19
2.3.1 Heatsink Size	20
2.3.2 Heatsink Mass	20
2.3.3 Package IHS Flatness	21
2.3.4 Thermal Interface Material	21
2.4 System Thermal Solution Considerations	22
2.4.1 Chassis Thermal Design Capabilities	22
2.4.2 Improving Chassis Thermal Performance	22
2.4.3 Summary	23
2.5 System Integration Considerations	23
3 Thermal Metrology	25
3.1 Characterizing Cooling Performance Requirements	25
3.1.1 Example	26
3.2 Processor Thermal Solution Performance Assessment	27
3.3 Local Ambient Temperature Measurement Guidelines	27
3.4 Processor Case Temperature Measurement Guidelines	30
4 Thermal Management Logic and Thermal Monitor Feature	31
4.1 Processor Power Dissipation	31
4.2 Thermal Monitor Implementation	31
4.2.1 PROCHOT# Signal	32
4.2.2 Thermal Control Circuit	32
4.2.2.1 Thermal Monitor	32
4.2.3 Thermal Monitor 2	33
4.2.4 Operation and Configuration	34
4.2.5 On-Demand Mode	35
4.2.6 System Considerations	35
4.2.7 Operating System and Application Software Considerations	36
4.2.8 THERMTRIP# Signal	36
4.2.9 Cooling System Failure Warning	36
4.2.10 Digital Thermal Sensor	37
4.2.11 Platform Environmental Control Interface (PECI)	38
5 Balanced Technology Extended (BTX) Thermal/Mechanical Design Information	39
5.1 Overview of the BTX Reference Design	39
5.1.1 Target Heatsink Performance	39
5.1.2 Acoustics	40
5.1.3 Effective Fan Curve	41
5.1.4 Voltage Regulator Thermal Management	42
5.1.5 Altitude	43
5.1.6 Reference Heatsink Thermal Validation	43
5.2 Environmental Reliability Testing	43
5.2.1 Structural Reliability Testing	43
5.2.1.1 Random Vibration Test Procedure	43
5.2.1.2 Shock Test Procedure	44
5.2.2 Power Cycling	45
5.2.3 Recommended BIOS/CPU/Memory Test Procedures	46
5.3 Material and Recycling Requirements	46
5.4 Safety Requirements	47
5.5 Geometric Envelope for Intel® Reference BTX Thermal Module Assembly	47
5.6 Preload and TMA Stiffness	48
5.6.1 Structural Design Strategy	48
5.6.2 TMA Preload verse Stiffness	48
6 ATX Thermal/Mechanical Design Information	51
6.1 ATX Reference Design Requirements	51
6.2 Validation Results for Reference Design	53
6.2.1 Heatsink Performance	53
6.2.2 Acoustics	54
6.2.3 Altitude	54
6.2.4 Heatsink Thermal Validation	55
6.3 Environmental Reliability Testing	55
6.3.1 Structural Reliability Testing	55
6.3.1.1 Random Vibration Test Procedure	55
6.3.1.2 Shock Test Procedure	56
6.3.2 Power Cycling	57
6.3.3 Recommended BIOS/CPU/Memory Test Procedures	58
6.4 Material and Recycling Requirements	58
6.5 Safety Requirements	59
6.6 Geometric Envelope for Intel® Reference ATX Thermal Mechanical Design	59
6.7 Reference Attach Mechanism	60
6.7.1 Structural Design Strategy	60
6.7.2 Mechanical Interface to the Reference Attach Mechanism	61
7 Intel® Quiet System Technology (Intel® QST)	63
7.1 Intel® QST Algorithm	63
7.1.1 Output Weighting Matrix	64
7.1.2 Proportional-Integral-Derivative (PID)	64
7.2 Board and System Implementation of Intel® QST	66
7.3 Intel® QST Configuration and Tuning	68

Intel E6700 Mechanical Design Guidelines - Page 103

Appendix E, Balanced Technology, Extended BTX System, Thermal Considerations

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